Troubleshooting Keyframes and Physics Issues with Reactor in 3ds Max

Published on January 08, 2026 | Translated from Spanish
Screenshot of 3ds Max showing the Reactor panel with the Unyielding option highlighted, along with a test animation.

When Reactor and Keyframes Decide Not to Get Along 🤯

In the fascinating world of 3ds Max, few things are more fun than watching Reactor completely ignore your carefully prepared keyframes. It's like scheduling a date and having your physics simulation show up late, drunk, and unwilling to cooperate. But fear not, there's a solution to this animation drama.

The Mysterious Case of the Object That Wouldn't Obey

When you try to make an object follow a spline and react physically with its environment, Reactor often behaves like that coworker who only does half their job. The key is finding the Unyielding option, which is like telling Reactor: "hey, these keyframes are orders, not suggestions".

Finding Unyielding in 3ds Max is like searching for headphones in a woman's purse: you know they're there, but the process is mysterious and frustrating.

Quick Guide to Taming Reactor

The Art of Making the Impossible Work

Veterans of foro3d.com know that working with Reactor requires the patience of a Buddhist monk and the persistence of a mosquito in summer. The combination of keyframes and physics will never be perfect, but with these tricks, at least it will stop looking like your object is having an epileptic seizure.

Remember that in 3ds Max, Euler is not just a dead mathematician, but an important option you probably should check. And if all else fails, you can always say you were creating a new style of abstract animation. 🎨

Pro tip: If Reactor still won't cooperate, threaten to replace it with Unity. It works 60% of the time, every time. 😼